Published in Physics World, 2 Mar 2010
The sands of Mars are a conundrum for physicists. Both dunes and ripples of sand appear to move around on the surface, and the stuff has fallen onto the deck of NASA’s Spirit Martian rover. Yet measurements of the Martian wind suggest that it rarely gets strong enough to lift even a single grain.
Now a researcher in the US believes to have solved this apparent contradiction. “While it is very difficult for the wind to lift sand grains, once the wind does become strong enough to start blowing sand on Mars, the sand will keep bouncing, even when the wind speed drops by up to a factor of 10,” explains Jasper Kok from the University of Michigan in Ann Arbor. […]
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